Sand screen



SAND S GREEN ///VE/Y 7'0? 14 H. We N652 m Dec. 16, 1930. w. H. WANGELINV Filed Oct. 15, 1928' Patented Dec. 16, 1930 l- WALTER n. wANGELIn, orfsrr. pours, MISSOURI J I,

saw) scnnnn Application fi1ed ctober 15, l9 28. Serial no. 312,44? .v

This invention relates generally to foundry apparatus and particularly to an iinproved sand screen adapted for ,use' in blending,

mixing, aerating, and generally preparing foundry sandfor use inmolds, the pre dominent object of the invention being to produce'an apparatus of this type which includes as an integral, internalpart thereof a sieve through which the sand acted on by 10 the apparatus passes during its passage through the apparatus, whereby the hard particles or foreign elements in the sand are separated therefrom so that only properly prepared, usable sand is discharged from-the? apparatus.

Prior to. this invention sand screens of the type to which my invention belongs have been produced and have been used in foundries, but these apparatus included rotatable. elements which rotated very slowly and the sand being acted on by the apparatus passed through the sieves thereof only by gravity.

Also-the nature of the sand screens formerly used necessitated that they be quite'large and therefore they wereordinarily not portable. The sand screens of the type referred to, due to the above and other" well known deficiencies in connection therewithpdid not operate with the desired efficiencyand this prevented such 'apparatusfrom being uni-; v'ersally used. i

Recognizing'the disadvantages in connection with the use of the sand screensformerly employed I have devised the sand screen disclosed herein which briefly stated in cludes a rotary sieve which moves at a very high rate of speed with the impellers by which the sand is discharged from the apparatus, whereby the sand beingacted on is forced through therotary sieve by cen trifugal forceand suction :of air. ;The ro tary sieve referred to isenclosed within the apparatus and when sand is introduced into apparatus by contact therewithf of the; im-- pellers is usable sand from whichhardparticles and foreign elementshave been removed. In addition to separating undesirable matter from the sandpassing through the apparatus the rotary sieve 'servestoaid the impellers in thoroughly blendingand mixing the sand so that saidisan d, after being aerated when projected through the air from the outlet of the apparatus, is erly prepared for use in molds. j "l Fig. 1 is a front elevation of my improved sand screen. i i

a: Fig. 2 is a verticalfsection of the sand screen illustrated inFig. 1. 4

Fig. 3 is a fragmentary vertical section showlngthe discharge outlet of theappara In the drawing, which illustrates one embodiment merely of the invention,A desig nates my improved sand screen generally, sa d sand screen including a housing B hav ing an'inlet' O' and an outlet'or discharge 1,

D. The housing'B is comprised ofa'front wall 1 and a rear wall 2 (Fig. 2) which "are, spaced apart from each'other, saiduwalls 1 and 2 being provided with flanges 3 and): respectivelythrough which suitable fasten ing devices, 5 pass to' secure saidwalls to a suitable support 6, which support, if desired, may be a portion of a truck or other portable device. Thewalls1 and 2 are provided with annular grooves 7 which are alin'ed with each other in the directionof the depth of the apparatus asshown in Fig. 2," a"nd 8 desig nates anannular or cylindrical wall the op posite edge portions of which are seated "in r the oppositely disposed grooves 7; Formed integral with or secured to the cylindrical wall 8 is a spout 9, said spout being extended outwardly from the cylindrical wall and constitutesthe outlet or discharge passageway of the apparatus; H

At the extreme upper portion of the apparatus I provide the front and rear walls 1 and 2 with cars 10, and lltdesignates a tie bolt which is extended through apertures formedin said ears, said'tie bolt having ahead portion at one-endthereoffand a screw-threadedportion at its opposite end which is adapted'to receive a nut, which head portion and nut contact with the cars 10 on the walls 1 and 2 in a manner to cause the upper portions of said walls to be drawn toward each other when the nut is screwed inwardly on the tie bolt. The spacing of the walls 1 and 2 at the lower portions thereof is such that in the absence of something preventing it, the cylindrical wall may be rotated, the opposite edge portions of said cylindrical wall moving relatively to the walls of the grooves 7 It is obvious in view of the arrangement just described that if it be desired to elevate or depress the outlet spout 9 to vary the angle of the stream of sand being discharged from the apparatus, this may be done by merely unscrewing the nut on the tie bolt 11. This will permit the upper portions of the walls 1 and 2 to move away from each other slightly thus relieving the frictional grip between the edge portions of the cylindrical wall 8 and the walls of the grooves 7 and permitting said cylindrical wall to be rotated to bring the spout 9 to the desired position. Then. the spout 9 has been properly positioned the nut on the tie bolt 11 will again be screwed inwardly on said tie bolt to cause the walls 1 and 2 to again frictionally grip the edge portions of the cylindrical wall 8 whereb Y accidental rotary movement of said wall Wlll be prevented.

The front wall 1 of the apparatus is provided with a large central opening 12 as shown clearly in Fig. 2, and 13 designates a plate which covers said opening. The plate 13 is secured to the front wall 1 by suitable fastening devices and said plate is provided with an opening 14 which serves as the inlet opening of the apparatus. Formed integral with the plate 13 or secured thereto is a chute or inclined trough 15 which leads to the opening 14 so that any material introduced into said chute will pass through said opening. At the lower portion of the plate 13 I provide an opening 16 which has associated with it a door 18 pivoted to the plate 13 at the point designated by the reference character 19. The pivoted door 18 is adapted to close the opening 16, and as will subsequently appear herein said door may be opended at the will of the operator to withdraw same from said opening. 20 designates a coil spring which is associated with the door 18 in a manner to cause said door to be normally maintained in a closed position, and 21 designates a connector which is connected at one of its ends to the door 18 and at its opposite end to a foot pedal (not shown) whereby said door may be moved to an open position when desired. 17 designates a stop which limits the downward movement of the portion of the door 18 which closes the opening 16'.

The rear wall 2 is provided with an extended bearing portion 2 in which a shaft 22 is supported in the usual manner by suitable roller bearings 23, the inner portion of said shaft 22 being extended inwardly into the 24 shall extend from the hub portion of the fiy wheel approximately to the peripheral face thereof as shown in Fig. 1. 25 designates a ring (Fig. 2), which is arranged at the forward edges of the arms 24. The

ring 25 is arranged in a plane which is parallel with the plane in which the plate 13 is arranged and said ring may be formed integral with the arms 24, or if desired, may be in the form of a separate element which is secured by suitable fastening means to said arms. Formed on each of the arms 24 at the outer end thereof is a portion of increased thickness, said portions being designated by the reference character 24 in the drawing, and removably fixed to said thickened portion of each arm by suitable fastening devices is a wear plate 26. The wear plates 26 are arranged so that the outer edges thereof are in close proximity to the inner face of the cylindrical wall 8 and said outer edges of said wear plates sweep along the inner face of said cylindrical wall when the rotor R is subjected to rotary motion. The forward edges of the arms 24 are inclined inwardly and downwardly from the position of the ring 25 to provide a space between the inner face of the plate 13 and said inclined forward edges of the arms 24 which space is approximately cone-shaped (Fig. 2).

27 designates the sieve of my improved sand screen which is fixed to the shaft 22 so that said sieve will rotate with said shaft, the connection between the sieve and the shaft bein effected by providing the shaft 22 with a ret uced screw-threaded portion 22 which is extended through an aperture formed through the rear wall 27 of the sieve on which screw-threaded portion 22 a nut 28 is screwed. The rear wall 27 of the sieve 27 is confined between the nut 28 and a shoulder 29 formed on the shaft 22 whereby said sieve is rigidly fixed to said shaft. The sieve 27 is located in the more or less conical space between the inclined forward edges of the arms 24 and the inner face of the plate 13, said sieve itself preferably being conical shaped as shown clearly in Fig. 2, and said sieve being provided with an annular seat 30 shaped to receive a corner portion of the ring 25. In view of this arrangement it is obvious that the forward portion of the sieve 27 is sup ported by the ring 25 whereby said sieve becomes a fixed part of the rotor R. The sieve is, of course, provided with a plurality of apertures through which the sand being acted through the opening 14: inrthe plate 13 into the interior of the cone-shaped sieve 27. The

sieve 27, together-with the other parts of the rotor R of the sand screen is rotating at this time and therefore the particles of sand of av size to permit it will pass through the apertures 31 of the sieveinto the interior of the housing of the apparatus where said sand will fall to the lower portion of the cylindrical wall 8. The arms 24 of the rotor R rotate rapidly in the direction indicated by the arrow in Fig. 3 and as a result thereof the wear plates 26 on said arms will contact with the sand in the bottom portion of the housing A and drive said sand forcibly through the discharge spout 9 whence it passes-through the air and is deposited in a heap some distance,

from the apparatus. Large particles'and for-' eign elements in the sand which are too large to pass through the a ertures 31 in thersieve will roll down the inc ined wall of saidsieve and will gather adjacent to the door 18 from which position they maybe removed by depressing the'foot pedal (not shown) to which the connector 21 is attached whereby said door 18 will be moved to an open position, thus permitting the large particles and foreign elements referred to pass through the opening 16.

When the apparatus is in operation the very rapid rotation of the arms 24 will result in air being drawn through the apertures 31 of the sieve into the interior of the housing of the apparatus, the rapidly moving arms 24; creating suction which results in such movement of air. It follows therefore that this passage of air through the apertures of the sieve, together with the centrifugal force created by the rapidly rotating parts of the apparatus, will cause the sand to befed rapidly and readily through said apertures whereby the sand is aerated and packing of Y sand at the apertures mentioned is prevented.

While I have illustrated and described the sieve of my apparatus as being approximately conical in shape I do not wish to be limited to the use of a sieve of such shape as my invention contemplates the .use of a sieve of any shape which may be located within the housing of the apparatus.

I claim:

1. A sand screen comprising a housing having inlet and discharge openings, an impeller arranged for rotary movement within said housing by which sand is forcibly driven from said housing through the discharge in said housing through which the sand passes before being acted on by said impeller,

said sieve being rotatable with said impeller, and a flywheel located within said housing immediately adjacentto and rotatable with said impeller. 2. A sand screen comprising a housing having inlet and discharge openings, one or more arms providing impellers arranged for rotary movement within said housing by which sand is forcibly driven from the housing through the discharge opening thereof, a sieve located within said housing through which the sand passes before being acted on by said impellers, and a fly wheel located within said housing to which said impellers are rigidly fixed, said sieve being rotatable with'said impellers and said fiy wheel and said impellers being located in close proxim-' ity to saidsieve.

3. A sand screen comprising a housing having inlet and discharge openings, an arm providing an impeller arranged for rotary movement within'said housing by which sand is forcibly driven from the housing through the discharge opening thereof, a sieve located within said housing through which sand passes before being acted on by said impeller, said sieve being rotatable with said impeller, anda fly wheel to which said impeller is rigidly fixed.

4:. A sand screen comprising a housing having inlet and discharge openings, one or more radial arms providing impellers arranged for rotary movement within said housing by which sand is forcibly driven from the housing through the discharge opening thereof, asieve movable with said impellers within the housing through which sieve sand passes before being acted on by said impellers, a fly wheel to which said impellers are rigidly.

fixed, and wear plates removably secured to said arms and serving as the portions thereof which contact with the sand to drive same from the housing.

opening thereof, a conical sieve located With;- 

